When Package Manager window is docked with Scene View, if Package Manager window resize then it cause Hierarchy window overlaps with Project window. Refer attached video

Steps to Reproduce:
1. Create a new project.
2. Window > Package Manager >Dock near scene window
3. Resize Package Manager window

Actual Result:
Hierarchy and Project window Overlaps when resizing the Package Manager Window

Expected Result:
Hierarchy and Project window doesn't get overalps on resizing Package Manager window

Reproducible on:
2020.2.0a15, 2020.2.0a1, 2020.1.0b13, 2020.1.0b1, 2019.3.0a1, 2019.2.18f1, 2018.4.23f1

Environment:
Windows 10 and macOS 10.15